The invention relates to a radio communication technique and, more particularly, to a technique for relieving access concentration on a radio base station (hereinafter referred as to a base station) from radio terminals.
In addition to a prior wired communication network, introduction of a radio communication network using radio terminals and a radio communication apparatus (hereinbelow, such a network is called a radio communication system) has been progressed. CdmaOne as a communication scheme using a CDMA technique, CDMA2000 and CDMA2000 1xEV-DO as upper standards thereof, and the like have been proposed.
In the radio communication system, the realization of a large capacity of communication data and a high communication speed is demanded for distribution of music, motion images or the like. In association with it, it is required that the base station has an advanced function and can cope with new functions. A frequency of software updating that cannot help temporarily stopping a call control service to the radio terminals is increasing.
In the radio communication system, the base station communicates with the radio terminals in an area called a cell where the base station can communicate. The base station has: a function for transmitting a message to force a radio terminal to reconnect to another cell by a broadcast to the radio terminals which are communicating in the cell (hereinafter referred as to a redirect function); and a function for broadcasting a message to control access frequency at which the radio terminals in its own cell make a new connection to the base station (hereinafter referred as to a new connection restriction function). The base station controls access from the radio terminals by using those functions.